MATLAB: How to make a structure unique

Question

emp.x=[]; 
emp.info=[];
emp.fit=[]; 
pop=repmat(emp,1,1);
pop(1).x=[1 2 3 4];
pop(2).x=[3 2 1 4];
pop(3).x=[1 2 3 4];
pop(4).x=[2 1 3 4];

How to make the above structure (pop) unique?

The result would be like the following figure.

Answer 1

You can achieve it using this script.

m = [];
for i = 1 : numel(pop)
    m = [m ; pop(i).x];
end
[~ , ia , ~] = unique(m , 'rows');
pop = pop(ia);